Review and Measurements of Benchmark AHB2 Amp

[RichB]

If you start with a 'distorted' source you will never hear anything other.

The greatest levels of distortion are from loudspeakers, then amplifiers then DAC's.

In general, it makes sense to remove variables. That is why Harman tests one speaker in a fixed location playing short selections from their playlist. Bad recording would not be revealing. Listening to loud 80 dB selections will tire the listener and it will be more difficult to discern differences.
As the evening goes on, expect results to muddy.

- Rich

 

[misterdog]

I was going to ask which mains cables you were feeding the amps with, but I see now.

 

[Archaea]

I was going to ask which mains cables you were feeding the amps with, but I see now.

you really like taking things out of context..

or can't read.

I'll let you explain which it is. That's the second time in an hour you've misrepresented something clearly explained otherwise.

 

[misterdog]

@Archaea - My problem with Amirm's reviews is that he's a measurement guy that appears to be into measuring things that are many times smaller than the human ear can subjectively hear and then whines about how poorly this or that model performs in those regards with almost no accountability as to what measurements have an actual "audible" effect on the output. From my conversation with him, he neither seems to care nor feels he should as he's purely into taking measurements and judging the "best" on the measurements rather than features, usability, the GUI, etc.

So why do the A/V crowd appear on here then I wonder.

 

[Pdxwayne]

Did you do these things first?


I don't have the Marantz 5508, I have the Denon X6700H, and my speakers are not full range speakers, so I need subwoofers.

But as to how revealing my own speakers are - they will be tested very shortly -- matter of fact. We shall both see.


https://www.audiosciencereview.com/...on-help-for-jbl-cbt-70j-1-measurements.17601/

I should probably make our blind test into its own post at AVS, so these types of things can be discussed without mucking up a owners/review thread with posts that some may consider off topic...

Yes, of cause I turned off all possible adjustment.

You can do the pure direct vs stereo comparison with your Denon too. Not exactly apple to apple, but why not? So your speakers are small? Doesn't matter. It can do at least 80 Hz and up, right?

 

[misterdog]

you really like taking things out of context..

-ROFL

Though this is a thread about the Benchmark AHB2 amplifier not some A/V comparison between Denon and Marantz.........

 

[Angsty]

Did you do these things first?


I don't have the Marantz 8805 I have the Denon X6700H, and my speakers are not full range speakers, so I need subwoofers.

But as to how revealing my own speakers are - they will be tested very shortly -- matter of fact. We shall both see.


https://www.audiosciencereview.com/...on-help-for-jbl-cbt-70j-1-measurements.17601/

I should probably make our blind test into its own post at AVS, so these types of things can be discussed without mucking up a owners/review thread with posts that some may consider off topic...

The thread is already over a hundred pages long, stemming from the original review. Don’t worry about it - haters are going to hate regardless of where it’s posted. I found it fascinating and useful to challenge some of my preconceptions.

I might still get the AHB2, but I’ll know it’s just because I want it versus expecting a night and day difference. My system is above average, but my room still has average flaws. So a “real world” test is more meaningful to me than testing pure tones for audibility in lab-like conditions. My room probably makes more of a sonic difference than my amp.

 

[Frank Dernie]

The thing I like most about the AHB2 is its styling is so like the Hafler DH220 I had.

 

[anmpr1]

The thing I like most about the AHB2 is its styling is so like the Hafler DH220 I had.

And if John would only release his amp in a kit, like David did back in the day, then Frank Van Alstine could work an FET mod on it, making the AHB into a really great amp! (That's a joke, BTW)

 

[Frank Dernie]

And if John would only release his amp in a kit, like David did back in the day, then Frank Van Alstine could work an FET mod on it, making the AHB into a really great amp! (That's a joke, BTW)

Yes I built mine from the kit, and the preamp. It was a worthwhile saving and easy. No mods though.

 

[anmpr1]

Yes I built mine from the kit, and the preamp. It was a worthwhile saving and easy. No mods though.

Interesting that you judged Hafler amp styling to be attractive, and compared it to the Benchmark. I agree they have a similar form factor, but when it comes to amplifier cosmetics David Hafler was from the old school (where amps were typically hidden in a cabinet, not meant to be seen). In fact, in his assembly manual we find:

The DH-220 is most likely to be installed out of sight in most applications, since its power may be controlled by the AC switching of most audio preamplifiers...

Dave's early Dyna amps could be wired for switching with whatever PAS preamp one used, and of course we find this 'feature' in the now almost common 12V triggers one finds on many amplifiers.

The days of kits are memorable, but impractical in our modern era. First is liability. Next are closer circuit board tolerances that are not very suited for DIY assembly. It's really sad that many younger audiophiles (or even older) will not have the opportunity and old fashioned fun of it. But when you can buy something stamped out in the Orient for next to nothing, I suppose that it's just not worth it for the majority of consumers.

And finally, anent my Frank van Alstine quip--I give him credit for keeping the 'old stuff' alive. Nothing wrong with that at all. When he stops (I'm surprised he's still at it) another piece of the old-school era puzzle will be lost.

 

[Frank Dernie]

Interesting that you judged Hafler amp styling to be attractive

I wasn't clear. I didn't find the Hafler particularly attractive, or the Benchmark, I just have fond memories of it which makes me see the Benchmark in a kinder light than its styling deserves, it is form dictating function design which I consider the correct way of going about engineering.
That is what I like, not the visuals.

 

[RichB]

And if John would only release his amp in a kit, like David did back in the day, then Frank Van Alstine could work an FET mod on it, making the AHB into a really great amp! (That's a joke, BTW)

My piece of kit had some assembly required. I had to connect the source, power, and trigger cables, perfect

- Rich

 

[RichB]

I wasn't clear. I didn't find the Hafler particularly attractive, or the Benchmark, I just have fond memories of it which makes me see the Benchmark in a kinder light than its styling deserves, it is form dictating function design which I consider the correct way of going about engineering.
That is what I like, not the visuals.

The AHB2s as look like mini Parasound Halo amps, that were considerably better looking (IMO) than any ATI I owned.
The new Parasound styling has gold lettering (yuck). They seem to chasing the old Marantz look which even they abandoned.

The movement from AT6000 amps, removed heat, weight, transformer hum, and the move the AHB2s had WAF.
They are considered cute

- Rich

 

[okok]

topping why not make some amps as good as this, they done the dac and hp amps

 

[misterdog]

The days of kits are memorable, but impractical in our modern era. First is liability. Next are closer circuit board tolerances that are not very suited for DIY assembly. It's really sad that many younger audiophiles (or even older) will not have the opportunity and old fashioned fun of it.

Tom Christiannsen's Neurochrome amps are an easy build and measure close to N-cores.
His new 686 is close to the AHB2.
https://neurochrome.com/collections/power-amplifiers

Measured by Amir here.
https://www.audiosciencereview.com/...urements-of-neurochrome-modulus-286-amp.6443/

 

[anmpr1]

Tom Christiannsen's Neurochrome amps are an easy build and measure close to N-cores.

Yes. Kits are out there. I've built a few in the past couple of years. But it's not like the days of Scott, Eico, Dyna, HK. Even McIntosh sold a MacKit. My guess is that Hafler was really the last major kit producer. And you know what? There is no way I'd even attempt to build something like an AHB, even if I had the parts laid out along with a schematic and instruction manual.

It's like cars. Back in the days men worked on their cars. Now that's almost impossible, with new models.

I'm reminded of a post (in another thread) from @restorer-john who wrote about the latest and greatest Yamaha amps. That once the warranty is over you might as well buy another, from a fix it and repair it standpoint. He's probably more right than wrong.

And it's not just hi-fi. When my almost new and under warranty Fender modeling combo amp developed a problem, Fender sent me a new one via the local authorized repair center. The center told me it was on their 'do not fix' list. They certified the S/N as defective, and told me they pitch them in the trash. LOL

 

[Angsty]

I might still get the AHB2, but I’ll know it’s just because I want it versus expecting a night and day difference.

I am still wrestling with what WOULD create a night and day difference between competent amps. The blind shootout article could not identify consistent differences with music content. I recall several years ago hearing a big difference between my old Proton amp and my replacement Bryston. I also have “aural memory” of differences between my NAD C272 and the Bryston, but that was at least 10 years ago.

I’ll soon have 3 amps in the house again, so I’ll need to experiment. I probably won’t be able to do a blind comparison, but I’m curious enough to give it a shot. Hopefully, that will keep me busy enough to discourage me from dropping three grand on an AHB2 just to satisfy “curiosity” of how it might be better. I really don’t need another amp.

 

[Chippyboy]

I am still wrestling with what WOULD create a night and day difference between competent amps. The blind shootout article could not identify consistent differences with music content. I recall several years ago hearing a big difference between my old Proton amp and my replacement Bryston. I also have “aural memory” of differences between my NAD C272 and the Bryston, but that was at least 10 years ago.

I’ll soon have 3 amps in the house again, so I’ll need to experiment. I probably won’t be able to do a blind comparison, but I’m curious enough to give it a shot. Hopefully, that will keep me busy enough to discourage me from dropping three grand on an AHB2 just to satisfy “curiosity” of how it might be better. I really don’t need another amp.

As far back as 20+ years ago there was an article written by a well-regarded engineer who basically said all competently designed amps (operating within their respective power and impedance envelopes) sound identical. It was IIRC in reference to his review at the time of the then quite new Audiolab 8000A... which I subsequently bought. His article created quite a storm amongst the snake oil peddlers especially. Funny that ;-)

From my own experiences at the time, I was upgrading from a Mission (as it was then) Cyrus 1, to one of a Cyrus 2, Naim Nait or the Audiolab. I spent an entire evening playing different tracks over and over and over again across the 3 amps. I think I could *just* detect a difference between them, but certainly not to the extent that any one sounded better than the others... to my ears at least. It came down to which one I liked best, and the idea that the Audiolab measured superbly - and had useful things like tone controls - was what swung it.

When I think that these were pretty low end amps in the scheme of things, and yet even at that level the differences were miniscule. I can only imagine that the difference in more modern amps costing 5x or 10x as must are smaller still.

That said, I have just bought a new NAD M33. For me, it's got to the point where usability, looks, features etc are at least as important - if not more important - than sound quality.

Of course if you feel the need to put stands under your speaker cables <falls off chair laughing> and buy a £150 mains lead then this will likely fall on deaf ears. No pun intended.

 

[Kal Rubinson]

I am still wrestling with what WOULD create a night and day difference between competent amps.

I imagine that the only way one would find a "night and day difference between competent amps" is if they were designed for a vastly different purpose and, therefore, one would be inappropriate for the test system. Over the years, I have strained to discern subtle differences among competent and suitable amps and never found a real "night and day difference."

That said, the AHB2 is one where the discerned difference (compared to a few other competent amps) was consistent. There were, and are, many that I could happily live with.